1. Slide 1 of 23 Copyright Pearson Prentice Hall Biology

2. Slide 2 of 23 Copyright Pearson Prentice Hall 21-3 Ecology of Fungi

3. Slide 3 of 23 Copyright Pearson Prentice Hall 21-3 Ecology of Fungi The oldest known fungi fossils are about 230 million years old. Fungi may have helped early plants obtain nutrients and may have been essential to plants’ colonization of the land.

4. 21-3 Ecology of Fungi Slide 4 of 23 Copyright Pearson Prentice Hall All Fungi Are Heterotrophs Fungi rely on other organisms for energy. Many fungi are saprobes, which are organisms that obtain food from decaying organic matter. Other fungi are parasites, which harm other organisms while living directly on or within them. Other fungi are symbionts that live in close and mutually beneficial association with other species.

5. 21-3 Ecology of Fungi Slide 5 of 23 Copyright Pearson Prentice Hall Fungi as Decomposers What is the main role of fungi in natural ecosystems?

6. 21-3 Ecology of Fungi Slide 6 of 23 Copyright Pearson Prentice Hall Fungi as Decomposers Fungi maintain equilibrium in nearly every ecosystem, where they recycle nutrients by breaking down the bodies and wastes of other organisms.

7. 21-3 Ecology of Fungi Slide 7 of 23 Copyright Pearson Prentice Hall Fungi as Parasites What problems do parasitic fungi cause?

8. 21-3 Ecology of Fungi Slide 8 of 23 Copyright Pearson Prentice Hall Fungi as Parasites Parasitic fungi cause serious plant and animal diseases. A few fungi cause diseases in humans.

9. 21-3 Ecology of Fungi Slide 9 of 23 Copyright Pearson Prentice Hall Fungi as Parasites Plant Diseases Fungal diseases are responsible for the loss of approximately 15% of the crops grown in temperate regions of the world. In tropical areas, where high humidity favors fungal growth, the loss of crops is sometimes as high as 50%.

10. 21-3 Ecology of Fungi Slide 10 of 23 Copyright Pearson Prentice Hall Fungi as Parasites Examples of plant diseases caused by fungi include: Corn smut Wheat rust

11. 21-3 Ecology of Fungi Slide 11 of 23 Copyright Pearson Prentice Hall Fungi as Parasites Human Diseases Examples of fungus-caused disorders include: Athlete’s foot Ringworm Thrush

12. 21-3 Ecology of Fungi Slide 12 of 23 Copyright Pearson Prentice Hall Symbiotic Relationships What kinds of symbiotic relationships do fungi form with other organisms?

13. 21-3 Ecology of Fungi Slide 13 of 23 Copyright Pearson Prentice Hall Symbiotic Relationships Some fungi form symbiotic relationships in which both partners benefit. Two such mutualistic associations, lichens and mycorrhizae, are essential to many ecosystems.

14. 21-3 Ecology of Fungi Slide 14 of 23 Copyright Pearson Prentice Hall Symbiotic Relationships Lichens Lichens are symbiotic associations between a fungus and a photosynthetic organism. The photosynthetic organism is either a green alga or a cyanobacterium, or both.

15. 21-3 Ecology of Fungi Slide 15 of 23 Copyright Pearson Prentice Hall Symbiotic Relationships Structure of a Lichen

16. 21-3 Ecology of Fungi Slide 16 of 23 Copyright Pearson Prentice Hall Symbiotic Relationships The algae or cyanobacteria carry out photosynthesis, providing the fungus with a source of energy. The fungus provides the algae or bacteria with water and minerals and protects the green cells from intense sunlight.

17. 21-3 Ecology of Fungi Slide 17 of 23 Copyright Pearson Prentice Hall Symbiotic Relationships Mycorrhizae Fungi also form mutualistic relationships with plants. The associations of plant roots and fungi are called mycorrhizae. Mycorrhizae is essential for the growth of many plants.

18. - or - Continue to: Click to Launch: Slide 18 of 23 Copyright Pearson Prentice Hall 21-3

19. Slide 19 of 23 Copyright Pearson Prentice Hall 21-3 Which of the following is NOT true of fungi? a.Some of them perform valuable service as decomposers. b.Some of them have a beneficial association with plants. c.Some of them can make their own food. d.Some of them cause serious diseases of plants, animals, and humans.

20. Slide 20 of 23 Copyright Pearson Prentice Hall 21-3 Ringworm is caused by a a.worm. b.fungus. c.plant. d.protist.

21. Slide 21 of 23 Copyright Pearson Prentice Hall 21-3 Research on mycorrhizae shows that plants a.are not dependent on other organisms. b.are closely related to fungi. c.may depend on other organisms. d.are seriously damaged by fungi.

22. Slide 22 of 23 Copyright Pearson Prentice Hall 21-3 In a mutualistic relationship a.both partners benefit. b.one partner benefits. c.neither partner benefits. d.neither partners is affected by the other.

23. Slide 23 of 23 Copyright Pearson Prentice Hall 21-3 Lichens are symbiotic associations that might be formed between a.a fungus and an animal. b.a plant and a bacterium. c.a cyanobacterium and a plant. d.a fungus and an alga.

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